Covenant remnants are splinter factions originating from the former Covenant body and remain active after the dissolution of the Covenant,[2] though no single group uses the specific term "Covenant remnant" to refer to themselves.[3] These factions vary greatly in ethos and motives; while some consider themselves as upholding the legacy of the Covenant as it used to be,[1] others have been shown to pursue more extensive reforms or their own specific agendas. Although many former Covenant members discarded the Prophets' religion and the belief in the "Great Journey" altogether in the wake of the revelation of the truth about the Halos,[4] many Sangheili in particular have reverted to their species' ancient ways of worshiping the Forerunners and their technology,[5] while others continue to maintain their belief in the "Great Journey" free from the influence of the Prophets.[6] Thus, the various Covenant remnant factions range from pragmatic mercenaries to fanatical religious cultists.[1]

Unlike the Covenant at its height, the general scarcity of resources has forced many of the remnant factions to use whatever materials they can find. Intact capital warships are considered coveted assets among the splinter factions, as many ships were destroyed in both the Great Schism and the Human-Covenant War as well as a significant portion of the Covenant's infrastructure and shipyards remaining inactive following the wars.[7] Additionally, with the majority of the Huragok mysteriously disappearing, many former Covenant no longer possess the capacity to repair and maintain most of their equipment.[8] Still, select Sangheili armories have taken over the production of matériel formerly manufactured within High Charity and have even developed new assets such as the T-55 storm rifle.[9][10] Despite this, many remnant groups are forced to employ obsolete or second-hand military equipment and weaponry in the absence of the Covenant's extensive supply chain. On the other hand, black markets—many of them operated by Kig-Yar profiteering from the Covenant's end, and others by Yonhet—were flooded with former Covenant matériel after the war.[11] Because of their limited resources, some Covenant groups have resorted to terrorism to achieve their ends following the war.[12] While previously considered a major taboo among the Sangheili, some groups are also known to utilize human weaponry, namely nuclear weapons.[13]

Many Unggoy, Mgalekgolo, Yanme'e and Kig-Yar remained within either the Jiralhanae's or the Sangheili's respective command hierarchies and continued to serve their masters throughout the Great Schism.[16][17]

After the death of the Prophet of Truth and many of the Prophets at the hands of the Sangheili, the remaining San'Shyuum went into hiding, leaving a power vacuum within the remains of the Covenant.[18] Various high-ranked members of the fallen hegemony seized control of as many military assets as they could; many became independent warlords commanding their own factions, some of them claiming to be legitimate successors to the Covenant.[1] Others, including many Sangheili kaidons, hoarded ships and weapons for their own purposes while avoiding involvement in larger conflicts.[19]

Humanity was also entangled in the Covenant remnants' post-war power dynamics. Conducting its own operations unknown to the rest of the UNSC, the Office of Naval Intelligence armed Sangheili dissidents of the Servants of the Abiding Truth and even covertly attacked the Arbiter's forces to maintain the balance of power between the two factions. ONI was also indirectly responsible for the formation of one of the most prominent post-Covenant revival factions, led by the Sangheili Jul 'Mdama. After escaping ONI detainment on the shield world-based ONI research facility Trevelyan, 'Mdama learned of his wife's death during the Blooding Years and vowed revenge on the humans due to their involvement in his species' affairs. 'Mdama, assisted by Sangheili from a remote colony planet called Hesduros, formed a new Covenant and proceeded to go to the Forerunner world Requiem and wake the "living god" known as the Didact to assist them in eradicating all humanity.[5]

The greater Sangheili-Jiralhanae feud continued in the background for years in the wake of the Great Schism, taking its toll on both species.[18] While seemingly more subdued in the first months after the Schism's beginning,[20] the conflict began to intensify again as the years passed and the Jiralhanae's resources began to dwindle. This prompted them to raid Sangheili-held territories for foodstuffs and other supplies, as they were unable of obtaining the resources themselves due to their disorganized and barbaric nature.[21]

Several of the more fanatical splinter factions have resumed the practice of glassinghuman colonies after the end of the Covenant War. The colony of Cleyell fell victim to such an attack in 2556.[25]

In October of 2558, 'Mdama's Covenant suffered a disastrous setback when its leader was killed by Fireteam Osiris while engaging Promethean forces. 'Mdama's forces would continue in his name, including an attempt to secure the ONI research vessel Argent Moon and an attack on Arbiter Thel 'Vadam's keep, but were ultimately destroyed by a counter-attack by the Swords of Sanghelios against their last major stronghold on Sanghelios, Sunaion. While it is likely that other Covenant factions remained, 'Mdama's faction was the largest, and Created Guardians were deployed across the galaxy almost immediately afterward, rendering their status unknown.[26]

Arbiter Thel 'Vadam and then-Special Operations CommanderRtas 'Vadum of the Fleet of Retribution successfully rebelled against the San'Shyuum-led Covenant during the Great Schism, assassinating its remaining political leadership alongside the UNSC.[27][28] Following the conclusion of the Human-Covenant War, 'Vadam and his allies formally established the Swords of Sanghelios and sought to make peace with the humans. The Swords are the most prominent post-Covenant faction to abandon not only the Covenant religion but also question the Sangheili's traditional worship of the Forerunners as well, which has been a point of controversy among some of the more conservative Sangheili.[29][30] The Abiding Truth, in particular, consider 'Vadam and his allies blasphemers.[5]

The Servants of the Abiding Truth is an insurgent group formerly led by Sangheili religious extremist and former Field Master, Avu Med 'Telcam.[31] Unlike most of the post-Covenant factions, the Servants have their roots in an ancient order, mostly suppressed by the Prophets during the Covenant's reign and revived after the San'Shyuum were overthrown.[32] Outspoken in their opposition of the Arbiter and his abandonment of the worship of the Forerunners, the Abiding Truth launched an armed insurgency against 'Vadam in March 2553, assisted by elements of the human Office of Naval Intelligence.[33] 'Telcam was assassinated by SPARTAN-G059 in January 2558.

The Keepers of the One Freedom are a militant religious cult devoted to the worship of the Forerunners based on Venezia. The Keepers are unusual among post-Covenant factions in that they welcome human followers to their ranks, provided they swear to oppose the "heretic tyranny" of the Unified Earth Government. Because of this, the Keepers quickly gained popularity within the Outer Colonies after the Covenant War. As of July 2553, they were also supported by separatist elements within Gao's planetary government, namely minister Arlo Casille, who covertly supplied them with money and weapons.[34]

The Banished are a mercenary group led by the Jiralhanae warlord Atriox. They fought against the Covenant long before the Great Schism in the early 2540s,[35] and have consolidated a significant number of military assets in the wake of the Human-Covenant War. In 2559, they had a major presence on Installation 00 and clashed with the UNSC forces from the UNSC Spirit of Fire when the long-lost support vessel mysteriously stumbled upon the Ark.[36]

After the events of the Great war, Luro 'Taralumee used his previous station within the Covenant in an attempt to consolidate power for unknown reasons and is considered dangerous by the UNSC due to his zealous devotion to the Great Journey and adherence to Covenant ideals.[37]

Lydus is a Jiralhanae Chieftain leading a master-pack which emerged in a position of power among the Jiralhanae after the fall of the Covenant. In 2558, Lydus and the pack agreed to enter peace negotiations with the Swords of Sanghelios to exchange Jiralhanae resources for food, overseen by the UNSC.[21] However, the subsequent attack by 'Gajat's forces left these peace negotiations in doubt.

Sali 'Nyon was a former member of Jul 'Mdama's faction, until he decided that he was the true "Didact's Hand". After gaining followers from within 'Mdama's faction, he betrayed Jul and stole the UNSC's half of the Janus Key.[38] Despite this, one of his followers had a change of mind and stole his half of the Janus Key, delivering it to Dr. Halsey. Shortly after this, Jul's Covenant captured Sali 'Nyon and destroyed all of Nyon's hideouts, killing all his followers and ending his rebellion temporarily.[39] Months later during Operation: ATHENAAyit 'Sevi released Sali from custody, allowing Sali and his new followers to take over the Breath of Annihilation and escape from Jul 'Mdama's forces.[40] 'Nyon remained as the de facto "Hand of the Didact" after 'Mdama's assassination and the collapse of his Covenant at Sunaion.[41]

Since the collapse of the Covenant, Kig-Yar society has shown little to no change. It is still overwhelmingly matriarchal in nature and is prone to piracy.[42] Significant Kig-Yar activities have been recorded on planets such as Venezia and Ven III. Kig-Yar scavengers have also continued to occupy glassed human colonies, as in the case of Cleyell.

This ancient group was the very first Covenant splinter faction, created by Ussa 'Xellus and other Sangheili who opposed the Writ of Union. During the time of the Covenant's creation, the Sangheili and Reformist San'Shyuum had united to create the empire. Ussa and like-minded Sangheili who opposed this union, fled their homeworld as it was occupied by the newly formed Covenant empire. They had arrived at Shield World 0673 and continued to practise pre-Covenant Sangheili traditions for many generations since.

After the end of the war, several former Covenant members that were loyal to the Covenant during the Great Schism sought revenge against the Sangheili.[43] Predominantly composed of Jiralhanae, this faction was led by San'ShyuumTem'Bhetek and Boru'a'Neem. It is one of the few post-war factions to contain San'Shyuum, and to resume hostility against the Sangheili but not humanity.

This faction was founded on Hesduros by Jul 'Mdama, who initially started as a member of the Servants of the Abiding Truth but grew disillusioned with their religious zeal and willingness to collaborate with humanity even temporarily.[47] Despite the ostensibly religious trappings of the group and the genuine zeal of many of its members, 'Mdama himself does not view the Forerunners as gods, only projecting the façade of a religious leader to motivate his followers.[48] Since the events of the first Requiem campaign, Jul 'Mdama's faction was considered by the UNSC to be the biggest threat among the many Covenant remnant factions, and absorbed elements of one large faction,[46] spun off twosmaller groups,[1] and allied themselves with the Ur-Didact's Promethean constructs, and with the greatest mind of the UNSC: Dr. Catherine Halsey. During the Battle of Kamchatka in October 2558, this Covenant faction received three fatal blows: Halsey was rescued by Fireteam Osiris, the Prometheans betrayed their Covenant allies, and the leader Jul 'Mdama was assassinated. After this devastating event, the Covenant—temporarily led by Kitun 'Arach and other high ranking Sangheili—launched a final, desperate assault to Sanghelios, but it failed and the faction was destroyed by the Swords of Sanghelios.

On the former human outer colony of Carrow, now jointly-held between humans and Sangheili, a sea change in governance has come to Rak, the foremost Sangheili habitation on the planet. In 2558, an Sangheili known as Thars 'Sarov took power. Thars is utterly opposed to peace with humans and believes that sharing Carrow with them is impossible. Those loyal to him began to attack humans here and there, but it wasn't until July of 2558 that the first one was killed and hostilities between his group and the Carrow militia erupted.[50]

These groups dissolved before the Covenant dissolved, thus they are not genuine remnants. However, these were significant splinter groups and held the same or similar ideologies as later remnant factions.

This assembly of Sangheili forces was a short-lived predecessor to the more prominent faction led by Rtas 'Vadum. At the onset of the Great Schism, Imperial AdmiralXytan 'Jar Wattinree summoned all Sangheili to the base world Joyous Exultation for an emergency meeting. 'Wattinree revealed the Prophets' treachery to his comrades and issued a fleet-wide missive of an alliance among the Sangheili to destroy both the Prophets and their Jiralhanae allies. With the exception of Voro Nar 'Mantakree's fleet, the entirety of this force was destroyed by a UNSC NOVA bomb during the summit.[53] Meanwhile, the survivors were wiped out at Onyx by the Forerunner world's automated defenses.